Peters Amplification

Peters Amplification is a company located in Winnipeg, Canada which has established a reputation for building first-class electric guitar amplifiers.  All amplifiers are meticulously hand made with point-to-point wiring using turret boards, robust components, and mindful engineering.

Custom Single Channel Series HALO 50W model

The HALO comes in a vintage looking head shell and a black powder-coated steel chassis to house the electronics.  Its look pays homage to the vintage amps which inspired it, but also conveys a modern boldness representative of the amp’s innovative design.

The HALO covers clean, blues and classic overdrive with the familiar characteristics of many sought-after vintage amps while still having its own signature sound.  The HALO has a wide and powerful feature set including a master volume whose effectiveness is second to none; this means the amp doesn’t need to be played at loud volumes (and doesn’t require attenuators) to achieve natural sounding vintage overdrive.

Used as a normal "master volume amp"--by setting Volume 1 to a desired level then adjusting the Volume 2 for overall level--the HALO takes on more "bounce" and gets a wide range of "verge of breakup" sounds.  When using overdrive pedals, the amp will develop more gain/distortion than volume.

Used as a "non-master volume amp"--by turning Volume 2 all the way up and using the Volume 1 for overall level instead--this allows for maximum headroom and articulation.  Using overdrive pedals with the amp in this mode will provide for a volume boost as well as gain/distortion.

Using either of the above two approaches or a combination of both, the HALO provides versatility beyond what most people would expect from a lot of single-channel “clean” amps; however the rest of its feature set provides even further versatility.

Poweramp controls:

This section provides a superb amount of flexibility to the amplifier’s feature set.

Damping
Less damping (clockwise) gives a more aggressive/deeper sound while more damping (counterclockwise) gives a softer/mellower sound.  This control tailors the amp’s response with different speaker cabinets, or compensates for different acoustic environments.

Depth
Extra bass response generated by the output section of the amplifier instead of in the preamp.  It's big, warm and full, and is especially useful to help attain a "huge sound" at lower to moderate volumes.  This control is specifically tailored to suit the output section design with a friendly, useful range of operation.  Combining the use of this control with the use of the channels' standard EQ can allow for more tight/focused sounds or more warm/rich sounds; turning the channel's Bass control down and turning the Depth up provides a more rich overall sound without getting percussive in the low frequencies.

Presence
Extra treble response generated by the output section of the amplifier instead of in the preamp section.  Its range starts in the range of the HALO's "High" control and extends beyond to allow for a sharper overall sound and more clarity.  This control, along with the "Depth" and "Damping" controls, helps shape the overall sound and response of the amplifier with a specific cabinet and acoustic environment.  The first 2/3 of the range is gradual, making its setting easy without the amp suddenly becoming bright sounding.  The last 1/3 of its range is more drastic a change, for those who desire a lot of brightness from the amp.

Preamp EQ:

The preamp’s EQ is specifically designed for a very effective and friendly range of operation, without reducing drive in lower settings of any of the controls.

Low
Controls the overall amount of low frequencies the preamp produces.  Ensures that even the most thick sounding neck pickups can be used without the amp becoming "boomy", or provides enough bass in the right frequencies to make even the most vintage bridge single coils sound beefy. 

Mid
Controls the overall amount of midrange frequencies the preamp produces.  Adds just the right amount of body where needed and ensures the amp will always have the right balance in the mix.  This midrange isn't nasal or rude in its higher settings; it's beautiful and it sings.

High
Controls the overall amount of treble frequencies the preamp produces.  Has a very smooth sweep without removing much articulation in the lowest settings, or being piercing in the higher settings.

Preamp function switches:

These bring another level of versatility to the design.

Bright / Dark switch
This switch allows the HALO to take on a more articulate/defined sound, or a more warm/dark sound more suited to jazz guitar.

Boost switch
This switch adds complexity to the midrange and treble while extending the HALO's gain range to effectively provide smooth round blues/classic overdrive.

Volume controls:

Volume 1
This is the "gain" control for the HALO, but can also be used as a "master volume" if Volume 2 is reduced.  (See more below.)

Volume 2
This is typically used as the "master volume" for the HALO, but it can be left on full and then Volume 1 becomes the "volume" control, as though the amp were being used as a traditional "non-master volume" design.

Rear panel features:

Effects loop (send/return)
These two jacks provide a "patch point" after the preamp section for effects devices.  The "Send" jack alternately functions as a "slave out" for feeding to other guitar poweramps, or possibly to a mixing board via a cabinet emulation device.  (If the "Send" jack for a loop is used but the "Return" jack isn't used, the signal still feeds the amp's output section.)  The "Return" jack can also be used as "poweramp input" so that other preamps can be run into the output section of the amplifier.

Speaker Outputs
Output jacks to accommodate 4, 8 and 16 ohm speaker loads (including paralleled 16 ohm loads, and paralleled 8 ohm loads).

Full Power / Low Power switch
A function to allow the amplifier's output section to be reduced in power quickly and effectively.  "Full Power" is 100% of the amp's output power rating, "Low Power" is approximately 40% of the amp's output power rating.

Modern / Vintage switch
This feature gives the amp's output some "sag" which is characteristic of a tube rectifier, but this approach doesn’t use a tube rectifier so it adds reliability to the design.  "Modern" has a more forward/punchy sound/feel, while "Vintage" has a warmer more relaxed sound/feel.

Bias Adjust / test
Using a regular volt meter and small screwdriver, the amp can be biased for replacement output tubes quickly and easily without opening the amplifier.  There is a small access hole for the easy-to-adjust 15-turn bias potentiometer and to its right, three pin jacks for testing the bias setting during adjustment (a bias document on the Peters Amplification site walks the owner of the amp through the bias procedure).  The two red jacks represent each tube's "positive" reading point and the "common" reading point in the middle is black.  The default output tubes shipped with the HALO are EL34, but the amp can be biased easily to accept 6L6GC, 5881, KT66, KT77, KT88, or 6550 output tubes.

Halo Sound Clips:

Halo Clip 1
Halo Clip 2
Halo Clip 3